The present invention is directed to recording sheets suitable for use in printing processes. More specifically, the present invention is directed to recording sheets and processes for the use thereof, wherein the recording sheet is resistant to mildew in high humidity environments. One embodiment of the present invention is directed to a recording sheet which comprises a substrate, an image receiving coating, and a biocide.
Recording sheets, especially transparencies intended for use with aqueous inks, frequently comprise a substrate coated with a hydrophilic ink receiving layer which is of a material or a mixture of materials exhibiting good film forming characteristics as well as the ability to dry images in relatively short times, the capability of spreading dyes prior to drying, resistance to fingerprints, or other desirable characteristics. For example, U.S. Pat. No. 4,592,954 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a transparency for ink jet printing which comprises a supporting substrate and thereover a coating consisting essentially of a blend of carboxymethyl cellulose and polyethylene oxides. Also disclosed are papers for use in ink jet printing comprising a plain paper substrate and a coating thereover consisting essentially of polyethylene oxides.
In addition, U.S. Pat. No. 4,865,914 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a transparency which comprises a supporting substrate and thereover a blend comprising poly(ethylene oxide) and carboxy methyl cellulose together with a component selected from the group consisting of (1) hydroxypropyl cellulose; (2) vinylmethyl ether/maleic acid copolymer; (3) carboxymethyl hydroxyethyl cellulose; (4) hydroxyethyl cellulose; (5) acrylamide/acrylic acid copolymer; (6) cellulose sulfate; (7) poly(2-acrylamido-2-methyl propane sulfonic acid); (8) poly(vinyl alcohol); (9) poly(vinyl pyrrolidone); and (10) hydroxypropyl methyl cellulose. In addition, papers with the aforementioned coatings are disclosed.
U.S. Pat. No. 5,212,008 (Malhotra et al.), the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate; a first coating in contact with the substrate which comprises a crosslinking agent selected from the group consisting of hexamethoxymethyl melamine, methylated melamine-formaldehyde, methylated urea-formaldehyde, cationic urea-formaldehyde, cationic polyamine-epichlorohydrin, glyoxal-urea resin, poly (aziridine), poly (acrylamide), poly (N,N-dimethyl acrylamide), acrylamide-acrylic acid copolymer, poly (2-acrylamido-2-methyl propane sulfonic acid), poly (N,N-dimethyl-3,5-dimethylene piperidinium chloride), poly (methylene-guanidine) hydrochloride, poly (ethylene imine) poly (ethylene imine) epichlorohydrin, poly (ethylene imine) ethoxylated, glutaraldehyde, and mixtures thereof; a catalyst; and a polymeric material capable of being crosslinked by the crosslinking agent and selected from the group consisting of polysaccharides having at least one hydroxy group, polysaccharides having at least one carboxy group, polysaccharides having at least one sulfate group, polysaccharides having at least one amine or amino group, polysaccharide gums, poly (alkylene oxides), vinyl polymers, and mixtures thereof; and a second coating in contact with the first coating which comprises a binder and a material selected from the group consisting of fatty imidazolines, ethosulfate quaternary compounds, dialkyl dimethyl methosulfate quaternary compounds, alkoxylated di-fatty quaternary compounds, amine oxides, amine ethoxylates, Imidazoline quaternary compounds, alkyl benzyl dimethyl quaternary compounds, poly (epiamines), and mixtures thereof.
U.S. Pat. No. 5,254,403 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and an image receiving layer comprising a mixture of (a) a polymer capable of forming a latex and selected from the group consisting of poly (vinyl chloride), ethylene-vinyl chloride copolymers, poly (vinyl acetate), carboxylated poly (vinyl acetate), ethylene-vinyl acetate copolymers, polymers containing acrylate monomers, polystyrene, styrene-butadiene copolymers, carboxylated styrene-butadiene copolymers, butadiene-acrylonitrile copolymers, butadiene-acrylonitrile-styrene copolymers, and mixtures thereof; (b) a polysaccharide; and (c) a polymer containing oxyalkylene monomers.
Copending application U.S. Ser. No. 08/196,669, now U.S. Pat. No. 5,500,668, with the named inventors Shadi L. Malhotra, Kurt B. Gundlach, and Richard L. Colt, filed concurrently herewith, entitled "Recording Sheets for Printing Processes Using Microwave Drying," the disclosure of which is totally incorporated herein by reference, discloses a printing process which comprises (a) providing a recording sheet which comprises a substrate, at least one monomeric salt, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler; (b) applying an aqueous recording liquid to the recording sheet in an imagewise pattern; and (c) thereafter exposing the substrate to microwave radiation, thereby drying the recording liquid on the recording sheet.
Copending application U.S. Ser. No. 08/196,922, now abandoned in favor of OB/444,477, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Alcohols and Saccharides," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of monosaccharides, oligosaccharides, and mixtures thereof. Another embodiment of the present invention is directed to a printing process which comprises (a) providing a recording sheet which comprises a substrate, a material selected from the group consisting of monomeric alcohols, monosaccharides, oligosaccharides, and mixtures thereof, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler; (b) applying an aqueous recording liquid to the recording sheet in an imagewise pattern; and (c) thereafter exposing the substrate to microwave radiation, thereby drying the recording liquid on the recording sheet.
Copending application U.S. Ser. No. 08/196,927, now U.S. Pat. No. 5,451,466, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises (a) a substrate; (b) a coating on the substrate which comprises (i) a binder selected from the group consisting of (A) copolymers of styrene and at least one other monomer; (B) copolymers containing acrylic monomers and at least one other monomer; and (C) mixtures thereof; and (ii) an additive having a melting point of less than about 65.degree. C. and a boiling point of more than about 150.degree. C. and selected from the group consisting of (A) diphenyl compounds; (B) phenyl alkanes; (C) indan compounds; (D) benzene derivatives; (E) benzyl alcohols; (F) phenyl alcohols; (G) menthol; (H) aromatic amines; and (I) mixtures thereof; (c) an optional filler; (d) an optional antistatic agent; and (e) an optional biocide. Also disclosed is a process for generating images which comprises (1) generating an electrostatic latent image on an imaging member in an imaging apparatus; (2) developing the latent image with a toner which comprises a colorant and a resin selected from the group consisting of (A) copolymers of styrene and at least one other monomer; (B) copolymers containing acrylic monomers and at least one other monomer; and (C) mixtures thereof; and (3) transferring the developed image to a recording sheet which comprises (a) a substrate; (b) a coating on the substrate which comprises (i) a polymeric binder selected from the group consisting of (A) copolymers of styrene and at least one other monomer; (B) copolymers containing acrylic monomers and at least one other monomer; and (C) mixtures thereof; and (ii) an additive having a melting point of less than about 65.degree. C. and a boiling point of more than about 150.degree. C. and selected from the group consisting of (A) diphenyl compounds; (B) phenyl alkanes; (C) indan compounds; (D) benzene derivatives; (E) benzyl alcohols; (F) phenyl alcohols; (G) menthol; (H) aromatic amines; (I) aliphatic amines; (J) aldehydes; (K) aldehyde derivatives; and (L) mixtures thereof; (c) an optional filler; (d) an optional antistatic agent; and (e) an optional biocide.
Copending application U.S. Ser. No. 08/196,673, now U.S. Pat. No. 5,451,458, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises (a) a substrate; (b) a coating on the substrate which comprises (1) a binder selected from the group consisting of (A) polyesters; (B) polyvinyl acetals; (C) vinyl alcohol-vinyl acetal copolymers; (D) polycarbonates; and (E) mixtures thereof; and (2) an additive having a melting point of less than about 65.degree. C. and a boiling point of more than about 150.degree. C. and selected from the group consisting of (1) furan derivatives; (2) cyclic ketones; (3) lactones; (4) cyclic alcohols; (5) cyclic anhydrides; (6) acid esters; (7) phosphine oxides; and (8) mixtures thereof; (c) an optional filler; (d) an optional antistatic agent; and (e) an optional biocide. Also disclosed is a process for generating images which comprises (1) generating an electrostatic latent image on an imaging member in an imaging apparatus; (2) developing the latent image with a toner which comprises a colorant and a resin selected from the group consisting of (A) polyesters; (B) polyvinyl acetals; (C) vinyl alcohol-vinyl acetal copolymers; (D) polycarbonates; and (E) mixtures thereof; and (3) transferring the developed image to a recording sheet which comprises (a) a substrate; (b) a coating on the substrate which comprises (1) a binder selected from the group consisting of (A) polyesters; (B) polyvinyl acetals; (C) vinyl alcohol-vinyl acetal copolymers; (D) polycarbonates; and (E) mixtures thereof; and (2) an additive having a melting point of less than about 65.degree. C. and a boiling point of more than about 150.degree. C. and selected from the group consisting of (1) furan derivatives; (2) cyclic ketones; (3) lactones; (4) cyclic alcohols; (5) cyclic anhydrides; (6) acid esters; (7) esters; (8) phenones; (9) phosphine oxides; and (10) mixtures thereof; (c) an optional filler; (d) an optional antistatic agent; and (e) an optional biocide.
Copending application U.S. Ser. No. 08/196,679, now U.S. Pat. No. 5,589,277, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Amino Acids, Hydroxy Acids, and Polycarboxyl Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a paper substrate and a material selected from the group consisting of monomeric amino acids, monomeric hydroxy acids, monomeric polycarboxyl compounds, and mixtures thereof. Another embodiment of the present invention is directed to a recording sheet which comprises a paper substrate and an additive material selected from the group consisting of monomeric amino acids, monomeric hydroxy acids, monomeric polycarboxyl compounds, and mixtures thereof.
Copending application U.S. Ser. No. 08/196,607, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Amine Salts and Quaternary Choline Halides," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of monomeric amine acid salts, monomeric quaternary choline halides, and mixtures thereof.
Copending application U.S. Ser. No. 08/196,676, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Pyrrole, Pyrrolidine, Pyridine, Piperidine, Homopiperidine, Quinoline, Isoquinoline, Quinuclidine, Indole, and Indazole Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and an additive material selected from the group consisting of pyrrole compounds, pyrrolidine compounds, pyridine compounds, piperidine compounds, homopiperidine compounds, quinoline compounds, isoquinoline compounds, quinuclidine compounds, indole compounds, indazole compounds, and mixtures thereof.
Copending application U.S. Ser. No. 08/196,933, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Purine, Pyrimidine, Benzimidazole, Imidazolidine, Urazole, Pyrazole, Triazole, Benzotriazole, Tetrazole, and Pyrazine Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of purine compounds, pyrimidine compounds, benzimidazole compounds, imidazolidine compounds, urazole compounds, pyrazole compounds, triazole compounds, benzotriazole compounds, tetrazole compounds, pyrazine compounds, and mixtures thereof. Also disclosed is a recording sheet which consists essentially of a substrate, at least one material selected from the group consisting of purine compounds, pyrimidine compounds, benzimidazole compounds, imidazolidine compounds, urazole compounds, pyrazole compounds, triazole compounds, benzotriazole compounds, tetrazole compounds, pyrazine compounds, and mixtures thereof, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler.
Copending application U.S. Ser. No. 08/196,672, with the named inventor Shadi L. Malhotra, filed concurrently herewith, entitled "Recording Sheets Containing Oxazole, Isooxazole, Oxazolidinone, Oxazoline Salt, Morpholine, Thiazole, Thiazolidine, Thiadiazole, and Phenothiazine Compounds," the disclosure of which is totally incorporated herein by reference, discloses a recording sheet which comprises a substrate and a material selected from the group consisting of oxazole compounds, isooxazole compounds, oxazolidinone compounds, oxazoline salt compounds, morpholine compounds, thiazole compounds, thiazolidine compounds, thiadiazole compounds, phenothiazine compounds, and mixtures thereof. Also disclosed is a recording sheet which consists essentially of a substrate, at least one material selected from the group consisting of oxazole compounds, isooxazole compounds, oxazolidinone compounds, oxazoline salt compounds, morpholine compounds, thiazole compounds, thiazolidine compounds, thiadiazole compounds, phenothiazine compounds, and mixtures thereof, an optional binder, an optional antistatic agent, an optional biocide, and an optional filler.
While suitable for their intended purposes, a need remains for improved recording sheets. In addition, a need remains for recording sheets which enable the formation of images which do not fade subsequent to drying of the sheet. Further, a need remains for recording sheets which enable the formation of images which are stable under high humidity conditions. Additionally, a need remains for recording sheets which exhibit long image quality and stability under a wide range of humidity conditions while also exhibiting resistance to attack by microorganisms. A need also remains for recording sheets which exhibit high image quality and stability as well as resistance to mildew when stored in plastic folders (such as polypropylene folders) under high humidity and/or heat conditions.